 |
Different extrusion processes also require different cleaning processes for the process section of planetary roller extruders. Due to the 45° helical gearing and the resulting roller effect, which transports the extrudate forward in the extrusion direction, the planetary roller extruder is the processing machine with the highest self-cleaning capacity. The self-cleaning effect of the planetary roller extruder is superior to all other processing systems and is only slightly reduced by the damming of material in front of intermediate rings and stop rings and by the clearance between the toothing.
For example, in many extrusion processes in which non-reactive materials such as soft PVC, PE, soap or bitumen are extruded, the process section of an extruder only needs to be cleaned if it is to be dismantled. Even during interruptions in operation, cleaning may not be necessary because the few material residues remaining in the process section after emptying are simply melted on the next start-up and the process can simply be continued after a certain heating phase.
When processing reactive materials, e.g. thermosetting plastics or very sensitive materials, which would be destroyed during the heating process or possibly during recipe changes, the process section usually has to be emptied and cleaned for every interruption in operation.
In many extrusion processes, the process part can be freed of material residues by feeding a cleaning granulate. For an ideal cleaning of the process part, ENTEX has developed the new PURGING COMPOUND, which is now immediately available.
It has been specially developed for cleaning the process components of planetary roller extruders and consists of natural rubber granulate and some other components which improve the cleaning performance and flowability.
The PURGING COMPOUND is fed into the process section, e.g. through a connected dosing scale or a stuffing device, until the extruded natural rubber compound exits the extruder without material contamination. If the emerging natural rubber compound is not too contaminated with residual material from the extrusion process, it can be returned to the cleaning process.
In addition to its optimised cleaning performance, ENTEX PURGING COMPOUND also has the benefit of better shelf life compared to other commercially available natural rubber granulates. Since it does not tend to clump even after prolonged storage, it can easily be introduced into the process section via dosing devices and is very well drawn in. It can be used in the temperature range from approx. 40 °C to 200 °C. The new ENTEX PURGING COMPOUND can be used for many extrusion materials and processes and is also suitable for use in food extruders, side feeders and other extruder systems such as twin-screw extruders.
Breakdowns caused by insufficient or improper maintenance can cause production losses, high repair costs and long downtimes of the extrusion line. For this reason, regular maintenance - including the toothed components of the extruder - is essential.
